This invention generally relates to illuminated gauge dials. More particularly, this invention relates to a light guide for a gauge pointer.
Instrument panels, such as those utilized for automotive applications, utilize illuminated gauges and pointers to improve gauge readability and provide a desirable aesthetic appearance. In some applications it is desirable to mount different gauges on different planes while maintaining independent movement of the pointers associated with each of the separate gauges. In some instances a pointer for indicating on an outer gauge is not attached to rotate about a central point, but is instead driven about the circumference of the gauge.
Illumination of a pointer driven about an outside scale cannot be provided through a centrally arranged light guide. Therefore, a plurality of light emitting diodes are placed about the circumference of the gauge to emit light into the pointer. The pointer includes a reflective surface that directs light as desired.
Disadvantageously, some color LEDs are expensive, such as white and green, and therefore adding additional LEDs of these colors is not an economically desirable alternative. Further, even with a plurality of LEDs disposed about the outer circumference of the gauge, the uniformity of illumination can vary much more than is desired.
Accordingly, it is desirable to design and develop a device for uniformly illuminating a pointer movable outside of a scale that decreases material and assembly costs.